Callers who experience difficulty with an interactive voice response (IVR) system may become so frustrated that they hang up before accomplishing their objective. This can result in toward, and lost revenue for, the called party. Thus, there is a need to detect when callers are having trouble, and intervene on their behalf. The like considerations exist not only in IVR systems, but in any systems that require interaction with a user, such as Automatic Call Distribution (ACD) systems, for example.
In this context, users with cognitive and/or physical disabilities might have a harder time navigating a typical IVR or other interactive user interface than the general population. Therefore, disability access rules enforced by the FCC require support for people who are cognitively impaired. Specifically, the Code of Federal Regulations, 36 C.F.R. Part 1193.41(i), states the following: “Input, control, and mechanical functions shall be operable with limited cognitive skills. Provide at least one mode that minimizes the cognitive, memory, language, and learning skills required of the user.” This regulation implies that IVR systems should adjust their behavior to accommodate the needs of cognitively impaired users. Unfortunately, it is often not practical—and perhaps even illegal—to maintain a database that identifies specific caller IDs or specific accounts as belonging to someone who has a disability. The problem then is, how can an IVR system detect automatically that a user is impaired? A way of detecting need for assistance is to monitor a user's interaction with the system. Indeed, some IVR systems monitor key-press sequences in order to detect that a user is having problems. For example, it may be assumed that users need additional help when they frequently ask for menus to be repeated, or if they are observed to go down a branch of a menu, come back up, go down a different branch, and then come back up again. Key-press duration has been used to determine the action to be taken. For example, on an electric typewriter, it is common for the “key repeat” function to be triggered by holding down a key longer than is necessary for a single character to be typed. And on electronic watches, it is common for a programming mode change to be triggered by holding down a button. Such time-dependent controls are explicit components of the user interface. In the mid 1980s, studies were conducted by Telcordia Technologies (then named Bell Communications Research, Inc.) to determine whether measurements of inter-digit pauses while personal identification numbers (PINs) are being entered might help to detect when the PINs are being entered by someone other than their owners.